This invention relates to a weather seal device for the bottom of a door in a building.
It is common knowledge that doors which have been installed for a long time may shrink and warp and become poorly fitted so a substantial amount of outside air may leak into a building at the joint between the lower edge of the door and the sill or floor over which the door is hung. Sometimes doors are poorly fit during original installation so there is a substantial gap at the bottom. The draft that results makes the occupants of the building uncomfortable and it imposes a greater load on the heating system of the building.
A variety of devices have been proposed for making a seal between the bottom inside edge of a door and the floor or the doorsill. Most of these devices use solid or semisolid sealing elements which are somewhat effective when the door is closed, but they have the disadvantage of not being capable of clearing obstructions or adjusting to irregularities in the floor when the door is being swung open. In many households, a small carpet or mat is placed adjacent the door which may bunch up and impose a heavy drag on the door by virtue of the sealing element which is mounted on the door encountering the mat or rug.
A solution to the problem of the door seal encountering obstructions is found in prior art devices that use rollers to produce the seal. A prior door edge weather seal that uses rollers is shown in U.S. Pat. No. 370,207. In this patent, the seal comprises a plurality of roller segments which are stacked on a shaft over such length as to substantially equal the width of the door. The shaft is carried at the opposite ends of a flat spring which is under the edge of the door and presses the rollers into contact with the sill or floor.
Another prior seal is shown in U.S. Pat. No. 1,837,959. This seal comprises a solid roller having a length substantially equal to the width of the door. The roller is covered with a tube of carpeting material. Shafts extend from the ends of the roller. Mounting brackets are fastened to the door. Arms are pivotally connected to the brackets and the arms have vertical slots in which the shafts rest. The pivoting action of the arms and movement of the rollers in the slots permits gravity to act on the roller to effect a seal. The slots and pivotal action also enable the roller to adjust for any obstructions which may be encountered as the door is swung open.
Another prior seal is shown in British Pat. No. 693,763. It also uses a solid roller having a length about equal to the width of a door and has shafts which are carried in an angulated slot in door mounted brackets. A compression spring acts on the shafts in the slot to effect a seal and to allow the roller to yield upwardly if it encounters obstructions.
A characteristic of prior art roller type door weather seals is that they are always shorter in axial length than the width of the door. As a result, leaks still exist adjacent the ends of the roller. The reason the rollers are made short of the door width is that if they were made as long as or longer than the door is wide, they would swing into the adjacent wall or door frame at the hinge edge of the door when an attempt is made to swing the door through a substantial opening angle. It is apparent that the roller type weather seals of the prior art would be damaged by colliding with a wall or door frame if they were made as long as they should be to produce a complete seal across the width of the door at its bottom edge.
Outside doors are usually installed in original construction by craftsman who have the tools and skills for testing the way the door fits into its frame and sill and they shave or otherwise reshape the door and its sill or its frame until a good seal is obtained without the door fitting too tightly to be opened and closed easily. However, as doors age, they often shrink or distort and form a gap between their bottom edge and their sill which allows cold air to blow into the building. Householders may then be faced with the problem of building up or replacing the sill. Many householders do not have the strength for handling the door nor the skills nor tools for installing a new sill, door or frame. They will, however, ordinarily have the ability to install one of the new weather seal devices made in accordance with the invention hereinafter described.